Vim is an open source, command line text editor. Prior to 9.2.0846, set_sofo() in src/spellfile.c reuses sl_sal_first[] without resetting values left by set_sal_first(), so a crafted spell file containing an SN_SAL section before an SN_SOFO section causes under-counted mapping lists and attacker-influenced writes beyond a heap allocation. This issue is fixed in version 9.2.0846.
Weakness
A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Red Hat Enterprise Linux 10 | RedHat | vim-2:9.1.083-9.el10_2.20 | * |
| Red Hat Enterprise Linux 7 Extended Lifecycle Support | RedHat | vim-2:7.4.629-8.el7_9.2 | * |
| Red Hat Enterprise Linux 8 | RedHat | vim-2:8.0.1763-31.el8_10.7 | * |
| Red Hat Enterprise Linux 8 | RedHat | vim-2:8.0.1763-31.el8_10.7 | * |
| Red Hat Enterprise Linux 9 | RedHat | vim-2:8.2.2637-26.el9_8.21 | * |
| Red Hat Enterprise Linux 9 | RedHat | vim-2:8.2.2637-26.el9_8.21 | * |
| Red Hat Enterprise Linux 9.6 Extended Update Support | RedHat | vim-2:8.2.2637-22.el9_6.4 | * |
| Red Hat Update Infrastructure 5 | RedHat | rhui5/cds-kubernetes-rhel9:1789479916 | * |
| Red Hat Update Infrastructure 5 | RedHat | rhui5/cds-rhel9:1789479900 | * |
| Red Hat Update Infrastructure 5 | RedHat | rhui5/haproxy-rhel9:1789479891 | * |
| Red Hat Update Infrastructure 5 | RedHat | rhui5/installer-rhel9:1789482961 | * |
| Vim | Ubuntu | esm-infra-legacy/trusty | * |
| Vim | Ubuntu | esm-infra-legacy/xenial | * |
| Vim | Ubuntu | esm-infra/bionic | * |
| Vim | Ubuntu | esm-infra/focal | * |
| Vim | Ubuntu | jammy | * |
| Vim | Ubuntu | noble | * |
| Vim | Ubuntu | resolute | * |
| Vim | Ubuntu | upstream | * |
Potential Mitigations
- Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking.
- D3-SFCV (Stack Frame Canary Validation) from D3FEND [REF-1334] discusses canary-based detection in detail.
- Run or compile the software using features or extensions that randomly arrange the positions of a program’s executable and libraries in memory. Because this makes the addresses unpredictable, it can prevent an attacker from reliably jumping to exploitable code.
- Examples include Address Space Layout Randomization (ASLR) [REF-58] [REF-60] and Position-Independent Executables (PIE) [REF-64]. Imported modules may be similarly realigned if their default memory addresses conflict with other modules, in a process known as “rebasing” (for Windows) and “prelinking” (for Linux) [REF-1332] using randomly generated addresses. ASLR for libraries cannot be used in conjunction with prelink since it would require relocating the libraries at run-time, defeating the whole purpose of prelinking.
- For more information on these techniques see D3-SAOR (Segment Address Offset Randomization) from D3FEND [REF-1335].